1.

A small object of uniform density rolls up a curved surface with an initial velocity 'v'. It reaches upto a maximum height of (3v^(2))/(4g) with respect to the initial position . The object is

Answer»

hollowsphere
DISC
ring
solid sphere

Solution :The kinetic ENERGY of the rolling object is converted into potential energy at height `h (= (3v^2)/(4G))`
So by the LAW of conservation of mechanical energy , we have
`(1)/(2) mv^(2) + (1)/(2) I omega^(2) = Mgh`

`(1)/(2) Mv^(2) + (1)/(2) I ((V)/(R))^(2) = Mg ((3v^2)/(4g)) (because omega = (v)/(R))`
`(1)/(2) I (v^(2))/(R^(2)) = (3)/(4) Mv^(2) - (1)/(2) Mv^(2) , or I = (1)/(2) MR^(2)`
Hence the object is disc.


Discussion

No Comment Found